Apparatus for feeding molten glass.



0. A. BRIDGES.

APPARATUS FOR FEEDING MOLTEN GLASS.

APPLICATION FILED OC T{15.1913.

Patented Dec. 22. 1914.

WITNESSES ORVILLE A. BRIDGES, 0F ZANESVILLE, OHIO.

APPARATUS FOR FEEDING MOLTEN GLASS.

Specification of Letters Patent.

Patented Dec. 22, 1914.

Application filed October 15, 1913. Serial No. 795,208.

Be it known that I, ORVILLE A. Bnmons, a citizen of the United States, .and resident of Zanesville, in the county of Muskingum and State of Ohio, have invented certain new and useful Improvements in Apparatus for Feeding Molten Glass, of which the following is a specification.

This invention relates to feeding molten glass from a suitable source, as a continuous tank or other furnace, and one object is to provide improved and efficient means for feeding or discharging the glass in amounts required for .each individual article, thereby varying and accurately .proportioning the delivered quotas to the work in hand.

A further object is to provide for arresting and so retracting the discharging stream between delivering operations as to prevent stringing and dripping, such retraction being accomplished by suction which is derived preferably from the means utilized for feeding the glass.

lVhile' various means may be employed for supplying molten glass to the feeding mechanism, a desirable method for utilizing the latter consists in arranging the same in a dog-houseextension of a continuous tank furnace, the glass which enters such extension being refined and ready for working. By this means the refining and delivering of the glass may proceed simultaneously and continuously.

In the accompanying drawings, Figure 1 is a sectional elevation of the improved mechanism in position in a dog-house extension of a tank furnace, the forcing plunger and the valve mechanism being in position for starting the delivering operation. Fig. 2 is a sectional plan on line 22 of Fig. 1. Figs. 3, 4 and 5 illustrate different positions of the controlling valve.

Referring to the drawings, 2 designates a dog-house extension which communicates with the discharge end of tank furnace 3 through openings 4 and 5 in the furnace wall, the glass entering the dog-house through opening 5 and maintaining the same level therein as in the furnace. Elie flow of glass from the furnace may be stopped by placing a block 6 passage 53, as when the dog-house is to be emptied for changing or repairing the feeding inechanism, or when the feeding operation to be discontinued for such a period of time as to warrant putting the dog-house out of commission.

The feeding mechanism consists of a body 7 of refractory material seated on the floor of furnace extension 2,-being held in place by the overhanging blocks 8 inserted through openings 9 1n the dog-house side walls. Body 7 is formed with the open-top plunger cavity 10 and with the open-top gate or valve passage 11, the latter commu-,

nicating with the lower portion of the plunger cavity through port 12. The necklike extension 13 of body 7 is formed with discharge duct or canal 14 which is open to gate 11 in the plane of passage 12, in the present embodiment neck 13 extending upwardly above the glass level. with its extremity disposed downwardly so that the molten glass will discharge in a downward direction for conveniently depositing it in molds or other receptacles arranged therebeneath. Neck 13 extends outwardly over bridge wall 15 of the dog-house, but its discharge end is located inwardly fromblock 16 which forms the end wall of the upper portion of the dog-house, thereby providing an overhanging discharge space in which the temperature of the'neck extension may be maintained by the heat of furnace. While the described arrangement is desirable and efficient, it will be understood that the invention is not confined to any particular arrangement or direction of the discharge duct with reference to body 7 so long as proper communication is maintained between the duct and the body.

Operative in cavity 10 is plunger 17 and in gate 11 a valve 18, the plunger and. valve being coupled, respectively, to the pistons of cylinders 19 and 20. A pipe 21. is connected to the upper ends of the cylinders, with separate valves 22 and 23 controlling communication with the respective cylinders. A similar pipe 24 has its communication with the lower ends of the cylinders controiled, respectively, by valves 25 and 26. Pipes 21 and 24- operate to admit compressed air for either depressing or raising the piscase may be, and as exhausts for nder ends, as will be understood. 2 means may be empioyed for con i the admission and exhaust through said pipes, it being suflicient in connection with the present disclosure to note that the relative amounts of air supplied to either the upper or lower ends of the cylinders may be controlled by the valves as may be requiredv tor synchronizing the movements of the plunger and valve in the accomplishment of any desired operation of said parts. Indeed, it will be understood that various means may be employed for actuating the plunger and valve, and hence the invention is not restricted to the cylinder means here shown.

Valve 18 above its lower extremity 30 is slotted vertically to provide port 31 for es tablishing communication through gate or passage 11 between plunger cavity 10 and the interior of the dog-house, also between said cavity and duct 14. Port 31 is of, such length that it may at the same time be open to the top of body 7 and also open to' duct 14, as shown in Fig. 4. Or, as shown in Figs. 1 and 5,.the valve may be so positioned that its bottom portion 30 closes duct 14, at which time free communication is maintained between the plunger cavity and the molten glass zone at the exterior of body 7. In still another position the valve may close the molten glass inlet for chamber 10 and maintain the latter in communication with duct 14, as in Fig. 3.

In operation, the amount of glass forced into duct 14 is preferably determined by the length of the plunger stroke which, in turn,

is controlled by the air admitted to the up per end of cylinder 19. At the same time the downward movement of valve 18should, for the best results, be accomplished as quickly as is practicable in order to promptly establish communication between cavity 10 and duct 14 and permitonly a relatively small portion of .the glass to How back through valve port 31 into the dog house. In the upward or refilling stroke, the speed of the valve is such as will most accurately and effectively control the suction to which the glass in duct 14 is subjected at such time, for the purpose hereinafter described. If desired, however, the plunger stroke may remain constant and the discharge of glass be varied by varying the movement of the valve, so graduating the valve movement as to permit more or less of the glass to flow back into the dog house, as determined by the amount to be discharged through duct 14. A relatively slow movement of the valve will result in discharging an appreciable portion of the glass, while a more rapid lowering of the valve will more promptly close the upper end of gate 11 and more quickly establish communication be tween the plunger and duct 14. It is believed, however, that this method of control is not so effective as that obtained by vary ing the stroke of the plunger.

The arrangement is preferably such that communication is maintained; between the pl-unger'chamber and discharge duct during such brief portion of the upward or suctioncreating movement of the plunger as will 10 result in arresting the outward movement of glass through duct 14 and so appreciably retracting the arrested glass as to prevent it from stringing and dripping at the point of discharge. In practice, the periods between discharging operations are comparatively brief, usually not exceeding a few seconds, so that by arresting the movement and slightly retracting the glass, no difiiculty is experienced in completely separating the discharging operations. The effect of the slight retraction referred to is evidenced at the discharge extremity of the spout by the backward bulge a inthe forward face of the discharging stream A.

From the foregoing it will be seen that the ported valve not only controls the inflow or supply of glass to the plunger chamber during the up-strokes of the plunger, but also serves to very accurately control the direction of flow of the glass on the downstrokes, directing more or less of it into the discharging conduit and the remainder back into the dog-house as determined by the movement of the valve relatively to the plunger. Thus, the amount discharged at each operation may be accurately predetermined, with corresponding uniformity in the bulk and weight of glass contained in the manufactured .articles.

The present invention is not concerned with the disposition of the glass after it is severed at the discharge end of duct 14 by shears or other cut-off mechanism actuated manually or otherwise. And while the dog 105 house is of such form that molds, may be readily presented into which the severed .quotas of glass may drop, the discharged quotas may be disposed of or utilized in any other desired manner.

I claim: I

1. Glass feeding apparatus comprising a molten glass container, a body within the container and having a plunger cavity be neath the glass level, a plunger operative in the cavity, the body formed with. a valve passage which communicates with the plunger cavity and also with the glass container beneath the glass level, a discharge conduit communicating with thevalve passage in the plane of the bottom portion of the plunger cavity, a slotted valve adapted to reciprocate in the valve passage with the valve slot adapted in one position of thevalve to establish communication between the plunger cavity and the source of glass and in another position establish communication between the plunger cavity and both the source of glass and the outlet conduit and in another position establish communication 1,1a1,eoe I alone between the plungercavity and the outlet conduit, and means for synchronizing the movements of the valve and plunger.

2. Apparatus for feeding molten glass comprising a body recessed to form a plunger cavity, the body having inlet and outlet passages adapted to communicate with the cavity, valve means for controlling said passages, a plunger operative Within the 10 plunger cavity, fluid pressure cylinders having their pistons connected, respectively, to the plunger andv the valve means, and means for proportioning the amounts of fluid supplied to the respective cylinders.

In testimony whereof I aflix my signature 15 in' presence ofatwo witnesses.

ORVILLE A. BRIDGES.

Witnesses:

C. S. HosKmsoN, EDNA M. LINN. 

